The announcement said that copper sulfate will be applied to treat the water for leeches with the two day closure applying to swimmers, boaters, scuba divers, fishers, drinking, irrigation and livestock or pet watering.

Gomes told Record reporter Jeremiah Horrigan that the leech infestation raises questions about changes to the lake’s ecosystem.

He said the lake’s high acidity has always kept the lake free of aquatic life, but that recent years have seen an unintentional introduction of fish species — golden shiners and large-mouth bass — to the area.

The lower acid levels, he said, allow creepy crawly critters like the leeches to “thrive” and feast.